This invention relates to an acoustic detection scheme involving an array of microphone elements and associated electronics. The elements are arranged so as to differentiate between the sound generated by a desired acoustic source and that of an undesired source. The region of space from which these signals originate determine whether they are desired or undesired.
A specific embodiment of this invention relates to a microphone sound pickup system and, more particularly, to a system having multiple microphones with each microphone being individually actuable in response to sound coming from a predetermined region of space relative to the microphone.
Multiple microphone systems have inherent disadvantages. For example, in a conference room where several microphones are utilized by persons sitting at a conference table, each microphone picks up not only its respective speaker's voice, but the voices of others in the room as well as ambient noise and reverberations. Also, the number of microphones being used reduces the gain of the system before acoustical feedback occurs.
One solution to this problem is to hire an operator to monitor the people speaking and manually actuate only one microphone at a time to provide one microphone input to the amplifier/output system. This is costly and often the speakers act too quickly for the operator to follow.
It is therefore, an object of the present invention to provide a microphone system which automatically controls the "on" condition of a microphone channel in conjunction with the need of the associated talker.
It is also an object of the present invention to provide a multiple microphone system that automatically adjusts the gain of the system in accordance with the number of "on" microphone channels.
It is a further object of the present invention to provide an attentuated microphone signal in the "off" condition to smooth system operation, whose level is automatically adjusted according to the number of microphone channels.
It is a further object of the present invention to provide a microphone that automatically gates "on" and "off" in response to a talker's voice being received from a particular region of space relative to the microphone.
It is a further object of the present invention to provide a microphone system which is easily installed by a person lacking specialized or set-up knowledge of the system.
It is a further object of the present invention to provide a microphone system utilizing conventional wiring and being usable with other conventional sound reinforcement components.
It is a further object of the present invention to provide a control signal output for each channel to control external devices or functions.
It is still a further object of the present invention to provide control signal inputs to affect operation of each channel, such as muting, channel priority, channel override, and the like.